1. Field of the Invention
This invention relates to an automatic sheet feeding device for use in or with an image forming apparatus, such as a copier, a printer, and a facsimile apparatus, that records on a recording medium, such as paper, an OHP (overhead projector) sheet, and an envelope.
2. Description of the Related Art
FIG. 8 illustrates a laser-beam-printer recording apparatus using an electrophographic recording technique as a conventional apparatus. To improve reliability in this type of sheet feeding apparatus, a sheet is linearly conveyed (this type is hereinafter termed a straight type) to perform recording.
In the straight type, however, the space for inlet and exit units for a sheet are added to the main body of the apparatus, causing an increase in the space needed for installing the apparatus.
In order to overcome this problem, a U-like configuration as illustrated in FIG. 9 or an S-like configuration as illustrated in FIG. 10, in which a conveying path for a sheet is inverted to reduce the actual space needed to install the recording apparatus, has been mostly adopted.
A method has also been proposed in which a sheet is conveyed while grasping only an end portion of the sheet with a conveying roller and an obliquely-oriented roller and pressing a reference side of the sheet against a conveyance reference guide of the main body of an image forming apparatus in order to prevent oblique movement of the sheet.
An attempt to reduce the size of an apparatus, to provide high picture quality, and to reduce the production cost of the apparatus has been made using the above-described method. However, since a recording medium is conveyed while pressing a reference side thereof, a greater amount of worn powder of the recording medium is produced than in other conventional conveying methods.